Washington, Dec 10: Overcoming their rivalries, eight US tech giants have joined hands to launch a public campaign asking the Obama administration and the US Congress to put a check on government surveillance through internet.

All together, Apple, Google, Microsoft, Facebook, Yahoo, Twitter, LinkedIn and AOL issued an open letter to President Barack Obama and members of the US Congress calling for reforms and restrictions on government surveillance.

The heads of the eight companies including Google's Larry Page, Yahoo's Marissa Mayer and Facebook's Mark Zuckerberg endorsed the campaign.

"While the undersigned companies understand that governments need to take action to protect their citizens' safety and security, we strongly believe that current laws and practices need to be reformed," the CEOs said.

Arguing that surveillance has gone too far, the companies said they are improving encryption and fighting to limit surveillance requests besides asking for new legal changes to limit surveillance.

"The balance in many countries has tipped too far in favour of the state and away from the rights of the individual - rights that are enshrined in our Constitution. This undermines the freedoms we all cherish. It's time for change," the CEOs wrote.

The tech giants' campaign comes in the wake of former National Security Agency contractor Edward Snowden's revelations on the agency's vast surveillance databases, many of which are part of programmes with intelligence agencies in other countries.

The US law requires tech companies to cooperate with court-ordered surveillance programmes. The NSA is also known to use other means to snoop on e-mail and other communications.

The surveillance is hurting the companies' businesses around the world as they are viewed as working too closely with US intelligence.

"People won't use technology they don't trust. Governments have put this trust at risk, and governments need to help restore it," Microsoft's general counsel, Brad Smith said in a blog post.